Setting a default rounding specification

If you ever get tired of having to write peri_glue(..., rspec = your_rspec) and would rather just write peri_glue(...), you should find this vignette helpful.

library(periglue)

Setting a default with set_default_rounding_spec()

Build a rounding specification with round_spec() and the round_/format_ helper families, then pass it to set_default_rounding_spec(). All subsequent calls to peri_glue() and peri_value() will use it automatically.

rspec <- round_spec() |>
  round_using_decimal(digits = 5)

set_default_rounding_spec(rspec)

peri_value(pi)
#> [1] "3.14159"

Clearing the default

Pass NULL to revert to factory settings.

set_default_rounding_spec(NULL)

peri_value(pi)
#> [1] "3.1"

Saving and restoring

set_default_rounding_spec() invisibly returns the previous default, which makes it straightforward to save and restore around a block of code.

rspec <- round_spec() |> round_using_decimal(digits = 3)

old <- set_default_rounding_spec(rspec)
peri_value(pi)
#> [1] "3.142"

# Restore whatever was set before
set_default_rounding_spec(old)
peri_value(pi)
#> [1] "3.1"

Factory defaults vs. stored defaults

round_spec(force_default = TRUE) bypasses both the stored default and any periglue.* global options, always returning the factory settings. This is useful if you need a clean baseline to build from regardless of session state.

set_default_rounding_spec(round_spec() |> round_using_decimal(digits = 5))

# Ignores the stored default
round_spec(force_default = TRUE)$digits
#> [1] 1